--- title: "Lettermint for developers integrating transactional email" description: "Send transactional emails with a clean REST API, official SDKs and real-time webhooks. Built for developers, hosted in Europe. Get started in minutes." url: "https://lettermint.co/for/developers" --- # Lettermint for Developers You write the code, we handle email delivery. A clean REST API, official SDKs and webhooks that just work. Send transactional emails with confidence from European infrastructure. ## Built for developers, by developers Developer experience is at the core of everything we build. Predictable responses so you never have to guess. Bounces, failures and delivery status arrive in real time via webhooks. Always with clear error codes so you know what's going on. No endless docs to wade through. Clear explanations with code examples so you can get started fast. Support from developers, not a call center. No scripts, just someone who understands your stack and thinks along. - Official SDKs, a CLI and an MCP server - Real-time webhooks for delivery events - Send your first email within minutes - Open source SDKs on GitHub ## Easy integration SMTP has been around since 1982. Still works great and runs everywhere. Want more control? Official SDKs are available for Node.js, PHP, Laravel, Symfony, Python, Go, Java, .NET, Rust and Elixir. Authentication, retries and error handling included. Prefer calling the REST API directly? That works too. Working from the terminal? The CLI sends email, manages projects and tests webhooks. Managing infrastructure as code? The Terraform provider sets up projects, domains, routes and webhooks. And with the MCP server, your AI assistant can send email and check delivery for you. Don't feel like writing code? There is an official plugin for WordPress. And with Zapier and Make you can connect Lettermint to thousands of other apps without a single line of code. See all [integrations](https://lettermint.co/integrations.md) or the [documentation](https://lettermint.co/docs/). ## High deliverability A password reset should arrive instantly. Not after five minutes, and definitely not in spam. Our infrastructure delivers transactional emails fast and reliably. No mail server to set up, no IPs to warm up, no reputation to build. We handle deliverability, you can keep focusing on your product. Live delivery speed per mailbox provider is published on [Time to Inbox](https://lettermint.co/time-to-inbox-tti.md). ## Made in Europe Lettermint operates exclusively within Europe, on its own infrastructure. From our servers to our team, everything is European. Your emails and customer data remain within EU borders at all times. Read more about the [European approach](https://lettermint.co/european-email.md). - **100% GDPR compliant** - Your data never leaves Europe. - **Your data, your control** - Full ownership of your data. - **European infrastructure** - Built and hosted in Europe. ## Frequently asked questions ### Is there a free plan? Yes, with the Free plan you send 300 emails per month. No credit card required, no time limit. If 300 emails and one domain are enough for you, you never need to upgrade. See [pricing](https://lettermint.co/pricing.md). ### Which SDKs and integrations do you have? Official SDKs for Node.js, PHP, Laravel, Symfony, Python, Go, Java, .NET, Rust and Elixir, plus SMTP, the REST API, a CLI, an MCP server and a Terraform provider. For WordPress, Zapier and Make there are ready-to-use integrations. See all [integrations](https://lettermint.co/integrations.md). ### Do you have an MCP server for AI agents? Yes. Add Lettermint to Claude Code, Codex, Cursor or another MCP client, then log in with OAuth. There is no API token to paste. Your agent looks up what happened to an email, checks delivery stats, verifies DNS and manages domains, routes and webhooks, always within your own team permissions. Personal data in your emails is hidden by default, and sending stays blocked until your team turns that filter off. The MCP server runs on our European infrastructure. Read more about our [MCP server](https://lettermint.co/features/mcp.md) or in the [MCP documentation](https://lettermint.co/docs/mcp). ### How do webhooks work? Set up a webhook URL per route in the dashboard. You receive events like delivered, bounced, opens and clicks directly as a POST request, with automatic retries if your endpoint is unreachable. Learn more in the [webhook documentation](https://lettermint.co/docs/platform/webhooks/introduction). ### What happens if an email doesn't arrive? Emails can fail to arrive for different reasons: a full inbox, an invalid address or a temporary server error. Each situation has its own flow. Temporary errors are retried automatically. You can check the status of every email in the dashboard, through the API or in real time via webhooks. ### Can I create separate API keys per project? Yes, you can create a separate API key per project. It only works for domains within that project. Handy if you run multiple apps or environments and want to keep them separate. ### Where are my emails processed? All servers are located in Europe and your data never leaves the EU. No CLOUD Act risks, fully GDPR compliant. ### Do you have rate limits? The sending endpoints are not throttled. Whether you send 100 or 100,000 emails per hour, we won't hold you back. Your plan quota and any spend limit you set still apply. ### Can I also send newsletters and marketing emails? Yes, besides [transactional emails](https://lettermint.co/features/transactional-emails) Lettermint offers [broadcast emails](https://lettermint.co/features/broadcast-emails) for newsletters, campaigns and other marketing emails. All from the same European infrastructure. ## Ready to integrate? Send your first email within minutes. Clear docs, SDKs that work and support from developers who understand your stack. No hassle with mail servers, just build. [Start for free](https://app.lettermint.co/register).